Spark plug wrench

ABSTRACT

A spark plug wrench has a handle movably coupled through a Ushaped link to a pivot pin that extends across the opening at one end of a plug-engaging socket, with the upper ends of the link being pivotally attached to one end of the handle, so that a loose fitting universal joint is formed between the handle and the socket.

United States Patent Heim et al.

[is] r 3,670,605 [4 June 20,1972

[54] SPARK PLUG WRENCH [72] Inventors: Kenneth J. Heim, Douglaston; Fred F.

Rimmler, Manhasset, both of NY.

[73] Assignee: A. L. Doering Mfg. Corp., Bayside, N.Y.

[22] Filed: Jan. 26, 1971 21 Appl. No.: 109,809

[52]- U.S.Cl. .Q .Q ..8l/l25,8l/I77 UJ [51] ..'..B25b 13/02 [58] FieldofSearch ..81/l25, 177 U], 177.8, 177 PP [56] References Cited UNITED STATES PATENTS 1,498,713 7 6/1924 York ..81/l77 UJ 2,832,245 4/1958 Burrows... 1,358,037 11/1920 Thayer ..8l/177 UJ FOREIGN PATENTS OR APPLICATIONS 926,495 4/1947 France ..81/177 UJ Primary Examiner-James L. Jones, Jr. Attorney-Brumbaugh, Grayes, Donohue & Raymond [5 7] ABSTRACT A spark plug wrench has a handle movably coupled through a U-shaped link to a pivot pin that extends across the opening at one end of a plug-engaging socket, with the upper ends of the link being pivotally attached to one end of the handle, so that a loose fitting universal joint is formed! between the handle and the socket.

8 Claims, 3 Drawing Figures PATENTEDmzo 1912 E 1, inmlllll-lllwi INVENTORS KENNETH J. HEIM a FRED F. RI MMLER their ATTORNEYS SPARK PLUG WRENCH BACKGROUND OF THE INVENTION This invention relates to wrenches that are especially suited for inserting and removing automobile spark plugs located in hard-to-reach places.

Spark plugs are frequently located in hard-to-reach places in automobile engines, especially in V-8 engines where the plugs are disposed at an angle to the horizontal on both sides of the engine block. It is normally not possible to install or remove spark plugs with conventional crescent wrenches or similarly shaped tools. Moreover, an ordinary socket wrench is not suitable because the spark plugs are often obstructed by other parts of the engine which results in tight working quarters.

Variations of socket wrenches which have universal type joints have been developed to overcome these problems, but those wrenches usually have a handle with a large number of interjoined movable parts or are formed of specially cast or tooled components with close tolerances, both of which add to the construction costs of the wrench.

Most of these wrenches have a handle tightly attached to the socket portion of the wrench, and the handle is movable back and forth in relation to the axis of the socket. Usually, the handle is movable only in one plane and movement lateral to that plane is not possible. This is disadvantageous in removing spark plugs because oftentimes the plug is in a position where the obstructing engine parts are located within this plane, thereby making it difficult or impossible to turn the plug. This also can cause injuries to the hands of the user and add to the amount of time it takes to remove the plug.

Other spark plug wrenches have been developed which have handles that are movable in two planes or even three planes by providing additional close fitting links between the handle and the socket. However, even in these wrenches the handle is limited to movement in a fixed number of planes. Because of the concentration of engine parts near the plugs there may be parts obstructing all of these planes, thereby neutralizing any advantages gained byproviding the extra links. Usually the extra links have been specially cast or tooled to a close tolerance with regard to other parts of the handle,

which in turn greatly increases the construction costs of the wrench.

The great number of automobiles on the road today and the rising costs of service have resulted in an ever-increasing number of people who prefer to change spark plugs themselves, and an inexpensive and easily workable spark plug wrench would fill a standing need.

SUMMARY OF THE INVENTION To solve the problems discussed above, a novel and improved spark plug wrench has been developed. The wrench has a socket formed of a length of hexagonally shaped metal tubing which is dimensioned to conform to the nut incorporated in conventional spark plugs. A first pivot pin is attached near one end of the tubing and extends across the opening at that end. A handle formed of a length of metal rod with a rectangular cross section is movably attached to the socket through a U-shaped link.

The handle is snugly received by the upper ends of the U- shaped link and pivotally attached to it. With this snug fit, the handle can only move back and forth relative to the link in a plane parallel to its upper ends. However, the link is movable relative to the'socket because the first pivot pin is passed through an aperture formed between the bottom of the link and the end of the handle, thereby giving the handle and the link a wide range of lateral movement relative to the plane mentioned above. In addition, the link is dimensioned so that it, and the handle, can move back and forth along the first pivot pin as well as a short distance parallel to the socket axis, this latter feature giving the handle a greater flexibility of movement.

These four independent movements allow for a high degree of maneuverability of the handle so that spark plugs can easily be inserted into and removed from tight fitting locations. However, the distance between the inner faces of the upper ends of the link is only slightly larger than the diameter of the first pivot pin so that the amount of play between the handle and socket is kept to a minimum when the socket is turned.

In addition, an opening is provided in the end of the handle opposite the one to which the U-shaped link is attached, the opening being capable of receiving a cross bar turning element for providing greater leverage for turning the wrench. A rubber insert positioned within the socket engages and holds the porcelain portion of the spark plug so it will not be damaged.

A wrench of the type described above is sturdy and relatively inexpensive to produce. The novel and loose fitting linkage between the handle and the socket enables the wrench to be maneuvered in tight quarters better than comparable socket wrenches known in the art, and with a decrease in the cost and no reduction in the strength of the wrench.

DESCRIPTION OF THE DRAWINGS For better understanding of the invention, reference may be had to the following description of the preferred embodiment, taken in conjunction with the accompanying drawing, in which FIG. 1 is a front elevational view of the spark plug wrench with the top portion of the socket being partially broken away to show with greater clarity the connection between the U- shaped link and the pivot pin extending across the end opening of the socket, with broken lines being included to show the movement of the handle;

FIG. 2 is a side elevational view of the wrench with the top portion of the socket being partially broken away to show with greater clarity the connection between the U-shaped link and the pivot pin extending across the upper end opening of the socket and with the broken lines being included to show the lateral movement of the handle; and

FIG. 3 is a bottom elevational view taken along line 3 as shown in FIG. 1, showing primarily the hexagonal shape of the socket and the structure of the pivot pin that extends across the upper end opening.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1-3 of the drawing, the spark plug wrench is generally designated by reference numeral 10, and is formed primarily of a socket 12 with a handle 14 movably attached to it. The socket 12 is formed of a length of hexagonally shaped metal tubing which defines an open space 16 extending its entire length, the hexagon being dimensioned so that the distance between the inside faces of each pair of parallel sides is preferably about 13/16 of an inch. This shape and size is provided to conform to the nut incorporated in a conventional spark plug (not shown). Instead of forming the socket 12 from a length of hexagonally shaped tubing, a length of, for example, cylindrical shaped tubing of an appropriate size can be used with one end being stamped or otherwise formed into a hexagon or other suitable shape. The handle 14 is preferably formed of a length of a metal bar that is rectangular in cross section, although metal bars of other shapes may be used.

A pivot pin 18 is securely attached to the socket 12 near one end (the upper end as shown in FIGS. 1 and 2) and extends across the open space 16 near that end, passing through holes located in a pair of parallel sides of the socket 12. The handle 14 is attached to the socket 12 through a U-shaped link 20 in a way that allows the handle 14 to be movable in relation to the socket 12, as will be discussed in detail below.

The link 20 is pivotally attached to the handle 14 by a pivot pin 22 that passes through that end of thehandle l4 and the upper ends of the link 20. In this way a snug pivotal connection is provided between the handle 14 and the U-shaped link 20, which allows the handle 14 to pivot back and forth in a plane parallel to the upper ends of the link 20, as shown by the arrows 24 and broken lines in FIG. 1.

By attaching the link 20 to the handle 14 in this way, an aperture 26 is formed between the rounded lower portion of the link 20 and the end of the handle 14, with the handle 14 being attached to the socket 12 by passing the pivot pin 18 through the aperture 26. As shown in FIG. 2, the distance between the upper ends of the link 20 is slightly larger than the diameter of the pivot pin 18 so that the handle 14 and the link 20 can move laterally in relation to the pivotal movement shown by the arrows 24 (see FIG. 1), as shown by the arrows 28 and broken lines in FIG. 2. However, the fit between the link 20 and the pivot pin 18 is snug enough so that the socket 12 can be turned by the handle 14 without allowing too much play between them.

As shown in FIGS. 1 and 2, the vertical dimension of the aperture 26 is significantly larger than the diameter of the pivot pin 18 so that a loose fit is provided between the handle 14 and the socket 12. This loose fit allows the handle 14 to move back and forth parallel to the axis of the socket 12, as shown by the double-headed arrow 30 in FIG. 2, as well as allowing greater flexibility in the pivotal movement shown by the arrows 24. The width of the U-shaped link 20 parallel to the pivot pin 18 is shorter than the length of the pivot pin 18 so that the link 20 can move back and forth along the pivot pin 18 as shown by the arrows 32 in FIGS. 1 and 3. This latter feature, along with the large vertical dimension of the aperture 26, adds an extra degree of maneuverability to the wrench 10, which facilitates operation of the wrench in tight surroundings. In other words, the wrench has a handle that is freely movable in four different directions relative to the socket 12. In this way, a spark plug located in a hard-to-reach area can easily be inserted or removed despite obstructing engine parts.

In addition, an opening 34 is provided on the end of the handle 14 opposite the one to which the U-shaped link is attached, so that a cross bar 36, screwdriver, or other suitable member can be used in conjunction with the handle 14 for providing greater leverage for the wrench 10. A rubber insert 38 in the socket 12 engages and grasps the porcelain portion of the spark plug to protect this fragile part.

Thus, there is provided in accordance with the invention a novel and improved wrench that can be used to insert and remove spark plugs that are located in hard-to-reach or tight places. The embodiment of the invention described above is intended to be merely exemplary and variations and modifications of it obvious to those skilled in the art are contemplated as being within the spirit and scope of the invention as defined in the appended claims.

We claim:

1. A spark plug wrench comprising a work-engaging socket open at each end, one end of the socket being shaped and dimensioned for receiving a spark plug, a first pivot pin attached to opposite sides of the socket near the other end thereof and extending across the end opening, a bar-like handle for the wrench, a U-shaped link coupling the handle to the socket, the upper ends of the link fitting snugly over one end of the handle, a second pivot pin pivotally attaching the handle to the link so that the handle is capable of moving back and forth in a plane parallel to the upper ends of the U-shaped link, an aperture formed between the rounded bottom of the U-shaped link and the end of the handle, the first pivot pin passing through the aperture for coupling the handle to the socket, the handle being capable of moving laterally in relation to said plane parallel to the upper ends of the U-shaped link.

2. A wrench in accordance with claim 1, wherein the dimension of the U-shaped link parallel to the axis of the first pivot pin is shorter than the length of the first pivot pin so that the handle is capable of moving back and forth relative to the first pivot pin.

3. A wrench in accordance with claim 1, wherein the distance between the bottom of the U-shaped link and the end of the handle is larger than the diameter of the first pivot pin so that the handle is capable of moving back and forth parallel to the axis of the socket.

4. A wrench in accordance with claim 1, wherein said one end of the socket is hexagonal in shape.

5. A wrench in accordance with claim 1, wherein the end of the handle opposite the U-shaped link has an opening formed therein for receiving a crossbar to facilitate turning of the socket.

6. A wrench in accordance with claim 1, wherein a rubber insert is provided in the socket to grasp the porcelain portion of the spark plug.

7. A spark plug wrench comprising a work-engaging socket open at each end, one end of the socket being hexagonal in shape for receiving a spark plug, a first pivot pin attached to opposite sides of the socket near the other end thereof and extending across the end opening, a bar-like handle for the wrench, a U-shaped link coupling the handle to the socket, the upper ends of the link fitting snugly over one end of the handle, a second pivot pin pivotally attaching the handle to the link so that the handle is capable of moving back and forth in a plane parallel to the upper ends of the U-shaped link, an aperture formed between the rounded bottom of the U-shaped link and the end of the handle, the first pivot pin passing through the aperture for coupling the handle to the socket, the handle being capable of moving laterally in relation to said plane parallel to the upper ends of the U-shaped link, the distance between the bottom of the U-shaped link and the end of the handle being larger than the diameter of the first pivot pin so that the handle is capable of moving back and forth parallel to the axis of the socket, the dimension of the U-shaped link parallel to the axis of the first pivot pin being smaller than the length of the first pivot pin so that the handle is capable of moving back and forth along the first pivot pin, and the end of the handle opposite the U-shaped link including an opening formed therein for receiving a crossbar to facilitate turning of the socket.

8. A wrench in accordance with claim 7, wherein a rubber insert is provided in the socket to grasp the porcelain portion of the spark plug. 

1. A spark plug wrench comprising a work-engaging socket open at each end, one end of the socket being shaped and dimensioned for receiving a spark plug, a first pivot pin attached to opposite sides of the socket near the other end thereof and extending across the end opening, a bar-like handle for the wrench, a Ushaped link coupling the handle to the socket, thE upper ends of the link fitting snugly over one end of the handle, a second pivot pin pivotally attaching the handle to the link so that the handle is capable of moving back and forth in a plane parallel to the upper ends of the U-shaped link, an aperture formed between the rounded bottom of the U-shaped link and the end of the handle, the first pivot pin passing through the aperture for coupling the handle to the socket, the handle being capable of moving laterally in relation to said plane parallel to the upper ends of the U-shaped link.
 2. A wrench in accordance with claim 1, wherein the dimension of the U-shaped link parallel to the axis of the first pivot pin is shorter than the length of the first pivot pin so that the handle is capable of moving back and forth relative to the first pivot pin.
 3. A wrench in accordance with claim 1, wherein the distance between the bottom of the U-shaped link and the end of the handle is larger than the diameter of the first pivot pin so that the handle is capable of moving back and forth parallel to the axis of the socket.
 4. A wrench in accordance with claim 1, wherein said one end of the socket is hexagonal in shape.
 5. A wrench in accordance with claim 1, wherein the end of the handle opposite the U-shaped link has an opening formed therein for receiving a crossbar to facilitate turning of the socket.
 6. A wrench in accordance with claim 1, wherein a rubber insert is provided in the socket to grasp the porcelain portion of the spark plug.
 7. A spark plug wrench comprising a work-engaging socket open at each end, one end of the socket being hexagonal in shape for receiving a spark plug, a first pivot pin attached to opposite sides of the socket near the other end thereof and extending across the end opening, a bar-like handle for the wrench, a U-shaped link coupling the handle to the socket, the upper ends of the link fitting snugly over one end of the handle, a second pivot pin pivotally attaching the handle to the link so that the handle is capable of moving back and forth in a plane parallel to the upper ends of the U-shaped link, an aperture formed between the rounded bottom of the U-shaped link and the end of the handle, the first pivot pin passing through the aperture for coupling the handle to the socket, the handle being capable of moving laterally in relation to said plane parallel to the upper ends of the U-shaped link, the distance between the bottom of the U-shaped link and the end of the handle being larger than the diameter of the first pivot pin so that the handle is capable of moving back and forth parallel to the axis of the socket, the dimension of the U-shaped link parallel to the axis of the first pivot pin being smaller than the length of the first pivot pin so that the handle is capable of moving back and forth along the first pivot pin, and the end of the handle opposite the U-shaped link including an opening formed therein for receiving a crossbar to facilitate turning of the socket.
 8. A wrench in accordance with claim 7, wherein a rubber insert is provided in the socket to grasp the porcelain portion of the spark plug. 